title: miR-29 promotes murine osteoclastogenesis by regulating osteoclast commitment and migration.
abstract: Osteoclast differentiation is regulated by transcriptional, post-transcriptional, and post-translational mechanisms. MicroRNAs are fundamental post-transcriptional regulators of gene expression. The function of the miR-29 (a/b/c) family in cells of the osteoclast lineage is not well understood. In primary cultures of mouse bone marrow-derived macrophages, inhibition of miR-29a, -29b, or -29c diminished formation of TRAP (tartrate-resistant acid phosphatase-positive) multinucleated osteoclasts, and the osteoclasts were smaller. Quantitative RT-PCR showed that all miR-29 family members increased during osteoclast differentiation, in concert with mRNAs for the osteoclast markers Trap (Acp5) and cathepsin K. Similar regulation was observed in the monocytic cell line RAW264.7. In stably transduced RAW264.7 cell lines expressing an inducible miR-29 competitive inhibitor (sponge construct), miR-29 knockdown impaired osteoclastic commitment and migration of pre-osteoclasts. However, miR-29 knockdown did not affect cell viability, actin ring formation, or apoptosis in mature osteoclasts. To better understand how miR-29 regulates osteoclast function, we validated miR-29 target genes using Luciferase 3'-UTR reporter assays and specific miR-29 inhibitors. We demonstrated that miR-29 negatively regulates RNAs critical for cytoskeletal organization, including Cdc42 (cell division control protein 42) and Srgap2 (SLIT-ROBO Rho GTPase-activating protein 2). Moreover, miR-29 targets RNAs associated with the macrophage lineage: Gpr85 (G protein-coupled receptor 85), Nfia (nuclear factor I/A), and Cd93. In addition, Calcr (calcitonin receptor), which regulates osteoclast survival and resorption, is a novel miR-29 target. Thus, miR-29 is a positive regulator of osteoclast formation and targets RNAs important for cytoskeletal organization, commitment, and osteoclast function. We hypothesize that miR-29 controls the tempo and amplitude of osteoclast differentiation.
authors.affiliation: From the Center for Molecular Medicine and.
authors.forename: Tiziana
authors.initials: T
authors.lastname: Franceschetti
authors.forename: Catherine B
authors.initials: CB
authors.lastname: Kessler
authors.forename: Sun-Kyeong
authors.initials: SK
authors.lastname: Lee
authors.forename: Anne M
authors.initials: AM
authors.lastname: Delany
mesh_terms: D020413:3' Untranslated Regions / Q000502:physiology; D000135:Acid Phosphatase / Q000235:genetics / Q000378:metabolism; D000818:Animals; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism; D002454:Cell Differentiation; D002460:Cell Line; D002465:Cell Movement / Q000502:physiology*; D002470:Cell Survival / Q000502:physiology; D003599:Cytoskeleton / Q000235:genetics / Q000378:metabolism; D044783:F-Box Proteins / Q000235:genetics / Q000378:metabolism; D000073979:F-Box-WD Repeat-Containing Protein 7; D020690:GTPase-Activating Proteins; D055785:Gene Knockdown Techniques; D006801:Humans; D007527:Isoenzymes / Q000235:genetics / Q000378:metabolism; D008297:Male; D051379:Mice; D035683:MicroRNAs / Q000235:genetics / Q000378:metabolism*; D010010:Osteoclasts / Q000166:cytology / Q000378:metabolism*; D000071681:Tartrate-Resistant Acid Phosphatase; D044767:Ubiquitin-Protein Ligases / Q000235:genetics / Q000378:metabolism
chemical_list: D020413:3' Untranslated Regions; D002352:Carrier Proteins; D044783:F-Box Proteins; D000073979:F-Box-WD Repeat-Containing Protein 7; C513272:Fbxw7 protein, mouse; D020690:GTPase-Activating Proteins; D007527:Isoenzymes; C547014:MIRN29 microRNA, mouse; D035683:MicroRNAs; C491402:Srgap2 protein, mouse; D044767:Ubiquitin-Protein Ligases; C000605510:ACP5 protein, human; D000135:Acid Phosphatase; C000605511:Acp5 protein, mouse; D000071681:Tartrate-Resistant Acid Phosphatase
keywords: 3′-UTR; Bone; Cell Differentiation; Cell Migration; MicroRNA; Osteoclast; Post-transcriptional Regulation; miRNA